The Old New Thing

Alton Brown book appearance report

January 24, 2005 Jan 24, 2005 01/24/05
Raymond Chen
Right on schedule, Alton Brown appeared at the Elliot Bay Book Company bookstore in downtown Seattle. One of my friends wondered aloud, "Wait a second, he's promoting his cookbook. How do you do a reading from a cookbook?" He didn't read from his cookbook. To an overflow crowd that probably violated a few fire codes, Alton Brown discussed...

Why are kernel HANDLEs always a multiple of four?

January 21, 2005 Jan 21, 2005 01/21/05
Raymond Chen
Not very well known is that the bottom two bits of kernel HANDLEs are always zero; in other words, their numeric value is always a multiple of 4. Note that this applies only to kernel HANDLEs; it does not apply to pseudo-handles or to any other type of handle (USER handles, GDI handles, multimedia handles...) Kernel handles are things you ...

Hyperlinking to Hutchison Whampoa Limited forbidden

January 20, 2005 Jan 20, 2005 01/20/05
Raymond Chen
Maybe they don't want people to find them. The copyright notice for the web site of Hutchison Whampoa Limited states, Copyright Hutchison Whampoa Limited. 2003. All rights reserved. No person, whether an individual or a body corporate, shall create or establish a hyperlink to the HWL Corporate Website by hypertext reference or imaging ...

CreateProcess does not wait for the process to start

January 19, 2005 Jan 19, 2005 01/19/05
Raymond Chen
The function creates a new process, but it doesn't wait for the process to get off the ground before returning. It just creates the process object and lets it go to do its thing. The Win32 process model is that each process initializes itself in context. When a process object is created, it is practically empty, save for enough information...

The importance of error code backwards compatibility

January 18, 2005 Jan 18, 2005 01/18/05
Raymond Chen
I remember a bug report that came on in an old MS-DOS program (from a company that is still in business so don't ask me to identify them) that attempted to open the file "". That's the file with no name. This returned error 2 (file not found). But the program didn't check the error code and though that 2 was the file handle. It then began ...

How did MS-DOS report error codes?

January 17, 2005 Jan 17, 2005 01/17/05
Raymond Chen
The old MS-DOS function calls (ah, int 21h), typically indicated error by returning with carry set and putting the error code in the AX register. These error codes will look awfully familiar today: They are the same error codes that Windows uses. All the small-valued error codes like ERROR_FILE_NOT_FOUND go back to MS-DOS (and possibly even ...

Cleaner, more elegant, and harder to recognize

January 14, 2005 Jan 14, 2005 01/14/05
Raymond Chen
It appears that some people interpreted the title of one of my rants from many months ago, "Cleaner, more elegant, and wrong", to be a reference to exceptions in general. (See bibliography reference [35]; observe that the citer even changed the title of my article for me!) The title of the article was a reference to a specific code ...